class Errs:
    error_index = {}

    @staticmethod
    def put(error_code: int, error_message: str) -> int:
        Errs.error_index[error_code] = error_message
        return error_code

    @staticmethod
    def err(error_code: int) -> str:
        return Errs.error_index.get(error_code, "未知错误")
